Modern methods for naturally increasing the size of the penis commonly involve some type of physical manipulation. In some cases this might take the form of manual stretching such as when performing specific penis exercises. Other times a device such as a penis extender is employed to generate a static and prolonged stretch of the fine penile tissue. In either instance, a palpable force is necessary to initiate the growth response that creates the increase in penis size. Here we'll look at the biological mechanisms behind those techniques that actually enables natural penis enlargement to occur.

Before we go into detail I'd like to make clear that understanding these scientific principles is in no way a prerequisite to achieving results. Men use penis stretching methods every day to increase the size of their penis without any advanced knowledge of the underlying processes at work. This article is merely an attempt to explain the biological functions that allow these methods to accomplish their goal.

The Basics

Most commercially available systems for penis enlargement make some brief mention about how results are achieved. They usually explain how the act of penis stretching opens up small spaces between cells which begins the process of cell division and multiplication. This ultimately results in the accumulation of tissue mass and subsequent penile size increases.

This explanation while general, does provide users with an adequate understanding of how natural penis enlargement is possible. Let's go a step further and now interject some scientific research to better comprehend what's occurring at the molecular level.

Satellite Cells

As explained in a recently published scientific journal:

"In undamaged postnatal muscle fibers with normal contraction and relaxation activities, quiescent satellite cells of resident myogenic stem cells are interposed between the overlying external lamina and the sarcolemma of a subjacent mature muscle fiber. When muscle is injured, exercised, overused or mechanically stretched, these cells are activated to enter the cell proliferation cycle, divide, differentiate, and fuse with the adjacent muscle fiber, and are responsible for regeneration and work-induced hypertrophy of muscle fibers."†

So physical interaction with muscle fiber, which includes exercising or other mechanically-induced stretching, triggers a response within otherwise normally inactive cells (called satellite cells). This begins the cycle of cell division and proliferation. But what mechanism actually translates this mechanical stimulation into the chemical signals necessary to activate the satellite cells? This from the same publication:

"Recent studies of satellite cells or single muscle fibers in culture and in vivo demonstrated the essential role of hepatocyte growth factor (HGF) and nitric oxide (NO) radical in the activation pathway. These experiments have also reported that mechanically stretching satellite cells or living skeletal muscles triggers the activation by rapid release of HGF from its extracellular tethering and the subsequent presentation to the receptor c-met. HGF release has been shown to rely on calcium-calmodulin formation and NO radical production in satellite cells and/or muscle fibers in response to the mechanical perturbation, and depend on the subsequent up-regulation of matrix metalloproteinase (MMP) activity. These results indicate that the activation mechanism is a cascade of events including calcium ion influx, calcium-calmodulin formation, NO synthase activation, NO radical production, MMP activation, HGF release and binding to c-met."†

As you can see, quite a lot happens within the tissues when mechanical incitement is initiated. In particular, the stimulation of satellite cells and muscle fibers causes the release and production of various chemical compounds.

But how does this interaction with muscle fibers relate to the penis, an organ that many would most certainly agree is not a "muscle."

Understanding Penile Physiology

Perhaps the biggest misconception about natural penile enlarging, particularly penis exercising, stems from a lack of understanding about the organ's physiology. The usage of the term "exercise" in regards to penis enlargement also adds to the confusion.

When one thinks of performing an exercise, it is fairly common to imagine some form of strenuous flexing done in order to build muscle. This is not the case with penis exercising. Instead this refers to the stretching and massaging of the penis using specific techniques. The penis does however contain muscle fibers which can be stimulated through these actions.

The Peripenic Muscle

The entire penile skin system and scrotum is lined with what is called the dartos muscle sheet. It is also known as the "peripenic muscle" because it wraps around the entire penis [see image].

This powerful muscle is composed of smooth muscle fibers that run parallel to the shaft of the penis. It is an involuntary and highly responsive muscle which contracts and relaxes in response to touch, temperature and sexual excitement.

The unique composition of the penis was noted in 1916 by a hospital pathologist by the name of Geoffrey Jefferson. Upon microscopic inspection of penile tissue samples, Mr. Jefferson was astonished by the amount of muscle tissue in his specimens and the complex connections of the peripenic muscle within the penis muscular structure. He also discovered that the development and strength of the entire muscle varied greatly from one individual to another.

As reported in his findings:

"The peripenic muscle is doubtless the cause of the remarkable rugosity usually exhibited by the removed prepuce or the prepuce under the stimulus of cold. These rugae are in the main arranged transversely, but innumerable minute ridges are superposed upon these. There can be no doubt but that the purpose of the muscle is to adapt the skin to the varying volume of the organ, as the changes are greater than could be accommodated by the elasticity of the skin alone."††

The significance of this observation relates to the method by which mechanical stimulation of the penis influences development of muscle fiber. If penile stretching were to only affect the outward covering of the shaft, any increases observed during the practice of penis enlargement would be constrained to the skin. Instead, physical manipulation directly impacts the muscle sheath itself which results in enlargement of the entire penis.

In Conclusion

The natural reactions that mechanical stimulation brings about within both cells and muscle fibers are intricate yet scientifically plausible. While this information may be nonessential for the vast majority of men seeking to improve penis size, I believe it does provides some valuable insight into the complex interactions that occur during the practice of penis enlargement.

Keep in mind, there is no magic involved in enlarging the penis... it's simply the body at work. When you begin to understand the responsiveness of the body to outside stimuli, it's easy to conceive how growth becomes the natural byproduct.

Personally, I like to think that there's a "well-hung" guy in each man just waiting to get out. Once you have the proper tools at your disposal, it's only just a matter of time before you achieve your goal.

Putting The Principles Into Action

If you'd like to learn more about how to utilize the applied sciences explained in this article, please read our SizeGenetics Review. This powerful system combines penis exercises with an external penile stretching device in order to achieve the fastest results possible.

Hi.. I am a 71 year old man with ED so I have a hard time getting and keeping my Erection even a semi Erection so my penis is really soft when I do my Jelqing Exercises, Am I wasting my time doing this Exercises ?? I have a Jelqing Device called the power Gym I love it but if it is not going to work for me then I'm going to stop using it. I even tried a cock ring didn't do any good and I can't take a Viagra every day. Do you think it will still work even if I'm soft.. Thanks

Left by Rick Bushaw on
May 14th, 2015

Jelqing is a simple technique so I'm not sure you actually need to use a device. While not all exercises require you to be erect, for the jelq you should maintain a partial erection for it to be effective. It does take time however to see results.

If exercising doesn't seem to be working for you then you may want to try a solution that doesn't require you to have an erection. Penile traction devices may give you much better results - read more here:

Recommended Products

The content on Penis-Resources.com is for informational purposes only and is not a substitute for professional medical or health advice, examination, diagnosis, or treatment. Your use of this website and its services indicates your agreement to our terms of use.